engine will not turn over
i just recently bought a 97 bonneville sse, great looking car, high mileage, but it doesn't show on the body. The guy i bought it off of couldnt get it to start and the number six cylinder was getting coolant in it. lo and behold it was the lower intake gasket that was bad. since i was already there the head gaskets looked pretty bad so i replaced them, come thanksgiving i got everything back together and started her up. it ran great but then began to blow out white smoke, changed the oil again cuz it was still a little milky. started it up again and the smoke disappeared, then all the sudden after 10 minutes it dies. trying repeatedly to get it to fire i killed the battery, i tried to jump it but no success. I am going to buy a new battery, but in anyones experience could there be a problem internally that caused it to shut off?